Effects of disease modifying agents and dietary intervention on insulin resistance and dyslipidemia in inflammatory arthritis: a pilot study

Dyslipidemia in rheumatoid arthritis: the possible mechanisms

Rheumatoid arthritis (RA) is an autoimmune inflammatory disease, of which the leading cause of death is cardiovascular disease (CVD). The levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-c), and high-density lipoprotein cholesterol (HDL-c) in RA decrease especially under hyperinflammatory conditions. It is conflictive with the increased risk of CVD in RA, which is called "lipid paradox". The systemic inflammation may explain this apparent contradiction. The increased systemic proinflammatory cytokines in RA mainly include interleukin-6(IL-6)、interleukin-1(IL-1)and tumor necrosis factor alpha(TNF-α). The inflammation of RA cause changes in the subcomponents and structure of HDL particles, leading to a weakened anti-atherosclerosis function and promoting LDL oxidation and plaque formation. Dysfunctional HDL can further worsen the abnormalities of LDL metabolism, increasing the risk of cardiovascular disease. However, the specific mechanisms underlying lipid changes in RA and increased CVD risk remain unclear. Therefore, this article comprehensively integrates the latest existing literature to describe the unique lipid profile of RA, explore the mechanisms of lipid changes, and investigate the impact of lipid changes on cardiovascular disease.

Insulin resistance and adverse lipid profile in untreated very early rheumatoid arthritis patients: A single-center, cross-sectional study in China

Objectives

This study aims to evaluate the presence and factors related to insulin resistance (IR) in untreated very early rheumatoid arthritis (RA) patients.

Patients and methods

Between June 2020 and July 2021, a total of 90 RA patients (29 males, 61 females; mean age: 49.3±10.2 years; range 24 to 68 years) and 90 age-, sex- and body mass index (BMI)-matched controls (35 males, 55 females; mean age: 48.3±5.1 years; range 38 to 62 years) were included. Homeostatic model assessment was applied to evaluate IR (HOMA-IR) and β-cell function (HOMA-β). Disease activity score 28 (DAS28) was used to estimate disease activity. Lipid profile, hemoglobin A1c (HbA1c), glucose, insulin, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) were measured. Logistic regression analysis was performed to investigate the relationship between the IR and clinical features of RA patients.

Results

The RA patients had higher HOMA-IR values (p<0.001) and adverse lipid profile. The IR was positively correlated with age (r=0.35, p<0.01), CRP (r=0.42, p<0.001), ESR (r=0.33, p<0.01), disease duration (r=0.28, p<0.01), and DAS28 (r=0.50, p<0.001). The DAS28, CRP and age, but not sex and menopausal status, were independently associated with IR.

Conclusion

Insulin resistance was present in untreated very early RA patients. The DAS28, CRP, and age were independent predictors for the presence of IR. Based on these findings, RA patients should be evaluated early for the presence of IR to reduce the risk of metabolic diseases.

Association of Rheumatoid Arthritis with Diabetic Comorbidity: Correlating Accelerated Insulin Resistance to Inflammatory Responses in Patients

Over the past two decades, with advancement of medical research and technology, treatments of many diseases including chronic disorders like rheumatoid arthritis (RA) have been revolutionized. Treatment and management of RA has been refined by advances in understanding its pathologic mechanisms, the development of drugs which target them and its association with various other chronic comorbidities like diabetes. Diabetes prevalence is closely associated with RA since elevated insulin resistance have been observed with RA. It is also associated with inflammation caused due to pro-inflammatory cytokines like tumour necrosis factor α and interleukin 6. Inflammation encourages insulin resistance and also stimulates other factors like a high level of rheumatoid factor in the blood leading to positivity of rheumatoid factor in RA patients. The degree of RA inflammation also tends to influence the criticality of insulin resistance, which increases with high activity of RA and vice versa. Markers of glucose metabolism appear to be improved by DMARDs like methotrexate, hydroxychloroquine, interleukin 1 antagonists and TNF antagonist while glucocorticoids adversely affect glycemic control especially when administered chronically. The intent of the present review paper is to understand the association between RA, insulin resistance and diabetes; the degree to which both can influence the other along with the plausible impact of RA medications on diabetes and insulin resistance.

Points to consider in cardiovascular disease risk management among patients with rheumatoid arthritis living in South Africa, an unequal middle income country

BACKGROUND

It is plausible that optimal cardiovascular disease (CVD) risk management differs in patients with rheumatoid arthritis (RA) from low or middle income compared to high income populations. This study aimed at producing evidence-based points to consider for CVD prevention in South African RA patients.

METHODS

Five rheumatologists, one cardiologist and one epidemiologist with experience in CVD risk management in RA patients, as well as two patient representatives, two health professionals and one radiologist, one rheumatology fellow and 11 rheumatologists that treat RA patients regularly contributed. Systematic literature searches were performed and the level of evidence was determined according to standard guidelines.

RESULTS

Eighteen points to consider were formulated. These were grouped into 6 categories that comprised overall CVD risk assessment and management (n = 4), and specific interventions aimed at reducing CVD risk including RA control with disease modifying anti-rheumatic drugs, glucocorticoids and non-steroidal anti-inflammatory drugs (n = 3), lipid lowering agents (n = 8), antihypertensive drugs (n = 1), low dose aspirin (n = 1) and lifestyle modification (n = 1). Each point to consider differs partially or completely from recommendations previously reported for CVD risk management in RA patients from high income populations. Currently recommended CVD risk calculators do not reliably identify South African black RA patients with very high-risk atherosclerosis as represented by carotid artery plaque presence on ultrasound.

CONCLUSIONS

Our findings indicate that optimal cardiovascular risk management likely differs substantially in RA patients from low or middle income compared to high income populations. There is an urgent need for future multicentre longitudinal studies on CVD risk in black African patients with RA.

Lipid management in rheumatoid arthritis: a position paper of the Working Group on Cardiovascular Pharmacotherapy of the European Society of Cardiology

Rheumatoid arthritis (RA) is associated with increased cardiovascular morbidity, partly due to alterations in lipoprotein quantity, quality and cell cholesterol trafficking. Although cardiovascular disease significantly contributes to mortality excess in RA, cardiovascular prevention has been largely insufficient. Because of limited evidence, optimal strategies for lipid management (LM) in RA have not been determined yet, and recommendations are largely based on expert opinions. In this position paper, we describe abnormalities in lipid metabolism and introduce a new algorithm for estimation of cardiovascular risk (CVR) and LM in RA. The algorithm stratifies patients according to RA-related factors impacting CVR (such as RA activity and severity and medication). We propose strategies for monitoring of lipid parameters and treatment of dyslipidaemia in RA (including lifestyle, statins and other lipid-modifying therapies, and disease modifying antirheumatic drugs). These opinion-based recommendations are meant to facilitate LM in RA until more evidence is available.

Evaluation of the glycemic effect of methotrexate in psoriatic arthritis patients with metabolic syndrome: A pilot study

Methotrexate (MTX) is a systemic immunosuppressant drug used for the treatment of psoriasis and psoriatic arthritis. Previous studies demonstrated a potential association between psoriasis and diabetes mellitus, obesity, atherosclerosis, hypertension, eventuating into metabolic syndrome. This study aimed at exploring the glycemic effects of MTX in psoriatic arthritis (PsA) patients. In this prospective cross-sectional study, 27 patients with PsA were evaluated. The status of PsA and presence of accompanying metabolic syndrome was determined by standard criteria and indices. Blood indicators including HbA1c, erythrocyte sedimentation rate, fasting blood sugar, total cholesterol, high-density lipoprotein, triglycerides, and C-reactive protein were examined before and 12 weeks after MTX therapy. There were no significant changes between HbA1c levels before and after MTX therapy in both genders (men: P=0.131, women: P=0.803). In addition, HbA1c levels in PsA patients with metabolic syndrome were not different before and after treatment (P=0.250). Finally, HbA1c levels did not change in PsA patients without metabolic syndrome before and after therapy (P=0.506). MTX in PsA patients does not appear to have hyperglycaemic effects in the short-term and can be safely used in patients with metabolic syndrome and diabetes.

Low disease activity (DAS28≤3.2) reduces the risk of first cardiovascular event in rheumatoid arthritis: a time-dependent Cox regression analysis in a large cohort study

OBJECTIVE

Systemic inflammation appears to contribute to the excess risk of cardiovascular disease (CVD) in rheumatoid arthritis (RA). The objective of this study was to investigate the effect of different levels of disease activity over time, particularly low disease activity and remission, on CVD risk in patients with RA.

METHODS

Data from the Nijmegen early RA inception cohort were used. The primary outcome was first CVD events within the first 10 years of follow-up. Cut points of the DAS28 for remission (<2.6) and low (≤3.2), moderate (3.2-5.1) and high (>5.1) disease activity were used. The effect of disease activity on CVD risk was analysed using Cox-proportional hazards regression with DAS28 as a time-dependent covariate and also conventionally with time-averaged DAS28 as the primary dependent variable.

RESULTS

Low DAS28 (≤3.2) was significantly associated with a reduced risk of CVD (HR 0.65, 95% CI 0.43 to 0.99) compared with DAS28 >3.2, both when included as a time-dependent covariate and as time-averaged DAS28 ≤3.2 (HR 0.52, 95% CI 0.33 to 0.81). Remission had a modest, non-significant protective effect against CVD (HR 0.67, 95% CI 0.43 to 1.07).

CONCLUSION

Results of this study suggest that low disease activity is sufficient to achieve a protective effect against CVD in RA. Apparently, remission defined as DAS28 <2.6 has no additional protective effect against CVD compared with low disease activity. Our results strengthen the use of tight control strategies in daily clinical practice to achieve low stable disease activity or remission in patients with RA as soon as possible.

Prevention of Stroke in Rheumatoid Arthritis

The risk of cerebrovascular disease is increased among rheumatoid arthritis (RA) patients and remains an underserved area of medical need. Only a minor proportion of RA patients achieve suitable stroke prevention. Classical cardiovascular risk factors appear to be under-diagnosed and undertreated among patients with RA. Reducing the inflammatory burden is also necessary to lower the cardiovascular risk. An adequate control of disease activity and cerebrovascular risk assessment using national guidelines should be recommended for all patients with RA. For patients with a documented history of cerebrovascular or cardiovascular risk factors, smoking cessation and corticosteroids and non-steroidal anti-inflammatory drugs at the lowest dose possible are crucial. Risk score models should be adapted for patients with RA by introducing a 1.5 multiplication factor, and their results interpreted to appropriately direct clinical care. Statins, angiotensin-converting enzyme inhibitors, and angiotensin-II receptor blockers are preferred treatment options. Biologic and non-biologic disease-modifying anti-rheumatic drugs should be initiated early to mitigate the necessity of symptom control drugs and to achieve early alleviation of the inflammatory state. Early control can improve vascular compliance, decrease atherosclerosis, improve overall lipid and metabolic profiles, and reduce the incidence of heart disease that may lead to atrial fibrillation. In patients with significant cervical spine involvement, early intervention and improved disease control are necessary and may prevent further mechanical vascular injury.

IL-6 Promotes Islet β-Cell Dysfunction in Rat Collagen-Induced Arthritis

The aim of this study was to explore the possible mechanism of rheumatoid arthritis- (RA-) related abnormal glucose metabolism. The model of collagen-induced arthritis (CIA) was established by intradermal injection of type II collagen into Wistar rats; complete Freund's adjuvant injections were used as the control group. Fasting plasma glucose (FBG) was measured by the glucose oxidase method. Fasting insulin (FIns) and the expressions of IL-6 were detected by ELISA. Islet caspase-3 was examined by immunohistochemistry. On day 17 after immunization, FBG of the CIA group showed an elevated FBG value compared with the control group. Meanwhile, the FIns of group CIA was lower when compared with the control group. Interestingly, the inflammatory cytokine IL-6 expression was significantly increased when compared with the control group. As expected, the abnormal glucose metabolism was accompanied by the increased IL-6 expression. Furthermore, in line with the upregulated IL-6 expression, the apoptosis related enzyme caspase-3 was also markedly increased. These data showed that the elevated FBG in CIA may be associated with the reduced FIns level secondary to the overapoptosis of pancreas islet cells induced by IL-6.

Association between lipid levels and major adverse cardiovascular events in rheumatoid arthritis compared to non-rheumatoid arthritis patients

OBJECTIVE

Lower levels of low-density lipoprotein (LDL) cholesterol may be associated with increased cardiovascular (CV) risk in rheumatoid arthritis (RA). This study was undertaken to determine whether the complex relationship between levels of LDL and high-density lipoprotein (HDL) cholesterol and CV risk is different in RA patients as compared to non-RA controls.

METHODS

Using data from a US health insurance plan (2003-2012), we conducted a cohort study that included patients with RA and non-RA control subjects matched with regard to age, sex, and index date. The nonlinearity of associations between lipid levels and incidence of major adverse CV events (MACE) was tested. We used multivariable Cox proportional hazards regression models to examine for an interaction between lipid levels and RA status in relation to the risk of MACE, after adjustment for CV risk factors.

RESULTS

In total, 16,085 RA patients and 48,499 non-RA controls were studied. The mean age was 52.6 years and 78.6% were women. The relationship between LDL cholesterol levels and incidence of MACE was nonlinear and similar between RA patients and non-RA controls (P for interaction = 0.72). No significant increase in CV risk was observed between the lowest quintile of LDL cholesterol levels (≤91.0 mg/dl) and the second, third, or fourth quintiles, whereas the highest quintile (>190.0 mg/dl) conveyed a 40% increase in risk of MACE (hazard ratio [HR] 1.40, 95% confidence interval [95% CI] 1.17-1.68). The relationship between HDL cholesterol levels and incidence of MACE was also nonlinear and similar between RA patients and non-RA controls (P for interaction = 0.39). Compared to the lowest quintile of HDL cholesterol levels, each successive quintile was associated with a reduced risk of MACE (HR 0.45, 95% CI 0.48-0.72 for lowest quintile [≤43.0 mg/dl] versus highest quintile [>71.0 mg/dl]).

CONCLUSION

The complex relationship between LDL cholesterol levels, HDL cholesterol levels, and risk of MACE was nonlinear in RA patients and also not statistically significantly different from that in an age- and sex-matched non-RA cohort.

Insulin resistance in rheumatoid arthritis: disease-related indicators and associations with the presence and progression of subclinical atherosclerosis

OBJECTIVE

Systemic inflammation and insulin resistance (IR) are linked, yet the determinants of IR and its impact on atherosclerosis in rheumatoid arthritis (RA) are incompletely understood. The aim of this study was to explore the prevalence of IR in RA and non-RA populations and investigate whether the associations of IR with measures of atherosclerosis differ between these groups.

METHODS

IR was quantified using the homeostatic model assessment of IR (HOMA-IR), and was compared between RA patients and demographically matched non-RA controls. Differences in the associations between the HOMA-IR index and the Agatston coronary artery calcium (CAC) score, ultrasound-determined intima-media thickness (IMT) of the common carotid artery (CCA) and internal carotid artery (ICA), and focal plaque in the ICA/carotid bulb were compared according to RA status.

RESULTS

Among the 195 RA patients and 198 controls studied, average HOMA-IR levels were higher in the RA group by 31%, and were consistently higher in the RA group regardless of stratification by demographic or cardiometabolic risk factors. While the HOMA-IR index was strongly and significantly associated with C-reactive protein (CRP) and interleukin-6 (IL-6) levels in the control group, the association was weaker in the RA group. Among RA patients, higher HOMA-IR levels were associated with rheumatoid factor (RF) seropositivity in men and women, and prednisone use in women only. Before adjustment, higher HOMA-IR levels were associated with all assessed measures of subclinical atherosclerosis in the control group only; associations were diminished and lost statistical significance after adjustment for cardiovascular risk factors. Among the RA patients, neither baseline nor average HOMA-IR levels were significantly associated with change in any of the atherosclerosis measures over an average of 3.2 years of followup.

CONCLUSION

Although IR was higher in RA patients than in non-RA controls, higher levels may not independently impart additional risk of atherosclerosis.

Rheumatoid cachexia revisited: a metabolic co-morbidity in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic inflammatory disease in which pro-inflammatory cytokines, including tumor necrosis factor (TNF)-α, play a crucial role. The chronic inflammation, combined with reduced physical activity, leads to muscle wasting whereas fat mass would be maintained; the resulting abnormal metabolic state is described as rheumatoid cachexia. Since the loss of muscle volume would be compensated by the increased fat mass, body mass index (BMI) is reported not to reflect the nutritional status in RA patients. The implication of rheumatoid cachexia for cardiovascular risk and clinical prognosis is not clearly understood, however, adequate control of disease activity in combination with appropriate physical exercise could be the most important strategy to control rheumatoid cachexia and related metabolic problems.

Cardiovascular disease risk amongst African black patients with rheumatoid arthritis: the need for population specific stratification

Rheumatoid arthritis (RA) enhances the risk of cardiovascular disease to a similar extent as diabetes. Whereas atherogenesis remains poorly elucidated in RA, traditional and nontraditional risk factors associate similarly and additively with CVD in RA. Current recommendations on CVD risk stratification reportedly have important limitations. Further, reported data on CVD and its risk factors derive mostly from data obtained in the developed world. An earlier epidemiological health transition is intrinsic to persons living in rural areas and those undergoing urbanization. It is therefore conceivable that optimal CVD risk stratification differs amongst patients with RA from developing populations compared to those from developed populations. Herein, we briefly describe current CVD and its risk factor profiles in the African black population at large. Against this background, we review reported data on CVD risk and its potential stratification amongst African black compared to white patients with RA. Routinely assessed traditional and nontraditional CVD risk factors were consistently and independently related to atherosclerosis in African white but not black patients with RA. Circulating concentrations of novel CVD risk biomarkers including interleukin-6 and interleukin-5 adipokines were mostly similarly associated with both endothelial activation and atherosclerosis amongst African black and white RA patients.

From guidelines to clinical practice: cardiovascular risk management in inflammatory arthritis patients

There exists significant evidence of increased risk of cardiovascular (CV) disease in rheumatoid arthritis (RA) patients in comparison with the general population. This finding has been supported by a number of guidelines recommending screening for CV disease risk in patients with the disease. However, the opportunity to identify and manage those patients at risk has been missed in both primary and secondary care. The success of CV risk management in diabetes patients provides a clear incentive to identify and actively manage CV risk in all RA patients as part of routine practice. This article provides an approach that shows how to assess for CV risk in standard clinical practice.

Independent associations of total and high molecular weight adiponectin with cardiometabolic risk and surrogate markers of enhanced early atherogenesis in black and white patients with rheumatoid arthritis: a cross-sectional study

INTRODUCTION

Whether adiponectin levels associate with atherogenesis in RA is uncertain. We examined the independent relationships of total and high molecular weight (HMW) adiponectin concentrations with cardiometabolic risk and surrogate markers of enhanced early atherogenesis in black and white patients with RA.

METHODS

We determined total and HMW adiponectin concentrations and those of endothelial activation molecules including soluble E-selectin, vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1) and monocyte chemoattractant protein-1 (MCP-1), in 210 (119 black and 91 white) RA patients. Associations were determined in potential confounder and mediator adjusted mixed regression models.

RESULTS

Total and HMW adiponectin concentrations related similarly to metabolic risk factors and endothelial activation. In all patients, total and HMW adiponectin concentrations associated paradoxically with high systolic, diastolic and mean blood pressure (partial R = 0.155 to 0.241, P ≤ 0.03). Ethnic origin did not impact on these relationships (interaction P ≥ 0.09). Total and HMW adiponectin concentrations associated with those of glucose in white and black patients respectively (partial R = -0.304, P = 0.006 and -0.246, P = 0.01). In black but not white participants, total and HMW adiponectin concentrations also related favorably to lipid profiles (partial R = 0.292 to 0.360, P ≤ 0.003 for HDL cholesterol concentrations, -0.269 to -0.299, P ≤ 0.006 for triglyceride concentrations and -0.302 to -0.390, P ≤ 0.002 for total-HDL cholesterol ratio) and the number of metabolic risk factors (partial R = -0.210 to -0.238, P ≤ 0.03). In white but not black patients, total and HMW adiponectin concentrations associated paradoxically with overall endothelial activation as estimated by a standard z-score of endothelial activation molecule concentrations (partial R = 0.262, P = 0.01 and 0.252, P = 0.02); in the respective models, the extent of effect of total and HMW adiponectin concentrations on endothelial activation was larger in white compared to black participants (standardized β (SE) = 0.260 (0.107) versus -0.106 (0.107), P = 0.01 and 0.260 (0.120) versus -0.100 (0.111), P = 0.02). The HMW-total adiponectin ratio related inconsistently to metabolic risk factors and not to endothelial activation.

CONCLUSION

In this study, total and HMW adiponectin concentrations associated with increased blood pressure parameters, and in white patients additionally with endothelial activation. The potential mechanism(s) underlying these paradoxical relationships between adiponectin concentrations and cardiovascular risk in RA merit further investigation.

Effects of disease modifying anti-rheumatic drugs on subclinical atherosclerosis and endothelial dysfunction which has been detected in early rheumatoid arthritis: 1-year follow-up study

OBJECTIVE

The study was designed to explore the effect of disease modifying anti-rheumatic drugs (DMARDs) on synovial inflammation as well as on atherosclerotic indices in patients with early rheumatoid arthritis (RA).

METHODS

The study included 35 early RA patients (disease duration <12 months). Inflammatory variables, like erythrocyte sedimentation rate (ESR) and high sensitivity C-reactive protein (hsCRP) were measured. Carotid intima-media thickness (cIMT) and endothelial dependent flow-mediated vasodilatation (ED-FMD) were measured by high-resolution ultrasonography. Disease activity of RA was assessed by disease activity score (DAS28) and quality of life was determined by Health Assessment Questionnaire-Disability Index (HAQ-DI) Score. All the above parameters were assessed both at baseline and follow-up after 1 year. Patients were treated with methotrexate (MTX), hydroxycholoroquine (HCQ) and sulfasalazine (SSZ) depending on their disease activity.

RESULTS

After a year of treatment, variables like ESR, hsCRP, DAS28 and HAQ-DI showed significant improvement (p < 0.0001 for each variable). However, there was no such significant change observed in the lipid profile after 1 year from the baseline. Average body mass index (BMI) of patients remained same at the one year follow-up. The cIMT values after 1 year decreased significantly [0.43 ± 0.08mm] from the baseline [0.50 ± 0.16mm] [p = 0.002]. Similarly, in case of FMD%, the post-1-year treatment values [7.57 (4.04-13.03)] improved significantly from the baseline [5.26 (2.9-10.6)] [p = 0.041].

CONCLUSION

Subclinical atherosclerosis and endothelial dysfunction are demonstrable features even in early RA which improved after therapy. Early intervention of RA with DMARDs not only controls the disease but also retards the atherosclerotic progression.

Metabolic syndrome in rheumatoid arthritis

Insulin resistance is an essential feature of the metabolic syndrome that has been linked to rheumatoid arthritis (RA). Understanding how inflammation arising in one tissue affects the physiology and pathology of other organs remains an unanswered question with therapeutic implications for chronic conditions including obesity, diabetes mellitus, atherosclerosis, and RA. Adipokines may play a role in the development of atherogenesis in patients with RA. Biologic therapies, such as TNF-α antagonists, that block proinflammatory cytokines have beneficial effects on the insulin resistance that is often observed in patients with RA.

Severe stroke: patient profile and predictors of favorable outcome

BACKGROUND

Severe stroke carries high rates of mortality and morbidity. The aims of this study were to determine the characteristics of patients who initially presented with severe ischemic stroke, and to identify acute and subacute predictors of favorable clinical outcome in these patients.

METHODS

An observational cohort study, Acute Stroke Registry and Analysis of Lausanne (ASTRAL), was analyzed, and all patients presenting with severe stroke - defined as a National Institute of Health Stroke Scale score of ≥ 20 on admission - were compared with all other patients. In a multivariate analysis, associations with demographic, clinical, pathophysiologic, metabolic and neuroimaging factors were determined. Furthermore, we analyzed predictors of favorable outcome (modified Rankin scale score of ≤ 3 at 3 months) in the subgroup of severe stroke patients.

RESULTS

  Of 1915 consecutive patients, 243 (12.7%) presented with severe stroke. This was significantly associated with cardio-embolic stroke mechanism (odds ratio [OR] 1.74, 95% confidence interval [CI] 1.19-2.54), unknown stroke onset (OR 2.35, 95% CI 1.14-4.83), more neuroimaging signs of early ischemia (mostly computed tomography; OR 2.65, 95% CI 1.79-3.92), arterial occlusions on acute imaging (OR 27.01, 95% CI 11.5-62.9), fewer chronic radiologic infarcts (OR 0.43, 95% CI 0.26-0.72), lower hemoglobin concentration (OR 0.97, 95% CI 0.96-0.99), and higher white cell count (OR 1.05, 95% CI 1.00-1.11). In the 68 (28%) patients with favorable outcomes despite presenting with severe stroke, this was predicted by lower age (OR 0.94, 95% CI 0.92-0.97), preceding cerebrovascular events (OR 3.00, 95% CI 1.01-8.97), hypolipemic pretreatment (OR 3.82, 95% CI 1.34-10.90), lower acute temperature (OR 0.43, 95% CI 0.23-0.78), lower subacute glucose concentration (OR 0.74, 95% CI 0.56-0.97), and spontaneous or treatment-induced recanalization (OR 4.51, 95% CI 1.96-10.41).

CONCLUSIONS

Severe stroke presentation is predicted by multiple clinical, radiologic and metabolic variables, several of which are modifiable. Predictors in the 28% of patients with favorable outcome despite presenting with severe stroke include hypolipemic pretreatment, lower acute temperature, lower glucose levels at 24 h, and arterial recanalization.

Impact of obesity and diabetes on arthritis: An update

The incidence of obesity and diabetes has been increased with alarming rate in recent years and became a common problem around the globe including developing as well as in developed countries with incalculable social costs. Obesity and type 2 diabetes are two common co-morbidities occur together. Obesity and diabetes is closely associated with many diseases, osteoarthritis, hypertension, certain form of cancer, sleep-breathing disorders and coronary heart disease. Impacts of obesity and diabetes (insulin resistance) on arthritis have been seen in patients that we associated with combination of various factors like increased availability of high- energy foods, genetic susceptibility and decreased physical activity in modern society. Arthritis is becoming pandemic around the globe and its occurrence with obesity and diabetes has been observed more common than ever. Combination of these two chronic conditions makes these diseases more vulnerable for human health. Till now very limited information is established about the pathological and mechanistic correlation among these health ailments. In this review article we aimed to survey the literature covering the influence of obesity and diabetes on arthritis pathology and tried to establish correlation with these diseases.

Traditional cardiovascular risk factors, inflammation and cardiovascular risk in rheumatoid arthritis

Multiple studies demonstrate an increased cardiovascular (CV) risk associated with RA compared with the general population. While part of this risk appears to be mediated by RA-specific factors, such as long-term inflammation, traditional CV comorbidities also play an important role. We review evidence from previous studies of the relationship between RA and traditional CV comorbidities such as dyslipidaemia, obesity, insulin resistance and diabetes, hypertension, cigarette smoking and physical inactivity. We examine the prevalence and consider the effect of inflammation and RA treatments on these risk factors. Finally, we discuss three widely used CV risk estimators, the Framingham Risk Score, Reynolds Risk Score and the Systematic Coronary Risk Evaluation, and their performance in patients with RA. The traditional CV risk factors that appear to differ significantly between RA cases and controls include insulin resistance, abnormal fat distribution, cigarette smoking and lack of physical activity. Dyslipidaemia, diabetes and hypertension may also be elevated in RA; however, the evidence is conflicting. Overall, we found that the majority of information regarding CV risk factors in RA stems from data collected as covariates for studies on CV disease. A gap in knowledge exists regarding detailed information on individual risk factors in RA, their prevalence and modifications that occur as a result of inflammation or treatment. More studies are needed to develop methods for accurate CV risk estimation in RA.

Diabetes mellitus risk in rheumatoid arthritis: reduced incidence with anti-tumor necrosis factor α therapy

OBJECTIVE

To examine the association of tumor necrosis factor α (TNFα) inhibitor use and the risk of developing diabetes mellitus in a rheumatoid arthritis (RA) inception cohort.

METHODS

Adults diagnosed with RA between January 1, 2001, and December 31, 2009, were identified (n = 1,881). Prevalent cases of diabetes mellitus (n = 294) were excluded. Information on sociodemographic data, medical history, body mass index (BMI), laboratory measures, and medications was collected from the electronic health record. Incident diabetes mellitus was defined using the 2010 American Diabetes Association criteria or physician-established diagnosis. Time-varying Cox proportional hazards regression models were used to adjust for age, sex, race, BMI, rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibodies (anti-CCP), erythrocyte sedimentation rate (ESR), and use of nonsteroidal antiinflammatory drugs (NSAIDs), glucocorticoids, hydroxychloroquine, and methotrexate.

RESULTS

A total of 1,587 incident RA patients without diabetes mellitus were included. The anti-TNFα users (n = 522) had a lower median age but greater baseline BMI; maximum ESR, RF, and anti-CCP positivity; and NSAID, glucocorticoid, or methotrexate use. The median followup time for the ever and never TNFα inhibitor users was 44.9 months (interquartile range [IQR] 23.7-73.0 months) and 37.1 months (IQR 16.3-65.1 months), respectively (P < 0.001). Of the 91 patients developing diabetes mellitus, 16 were ever and 75 were never TNFα inhibitor users, yielding incidence rates of 8.6 and 17.2 per 1,000 person-years (P = 0.048), respectively. Adjusting for covariates, the hazard ratio for incident diabetes mellitus in TNFα inhibitor users was 0.49 (95% confidence interval 0.24-0.99, P = 0.049) compared to the never users.

CONCLUSION

In this inception RA cohort, anti-TNFα use was associated with a 51% reduction in risk of developing diabetes mellitus.

Cardiovascular co-morbidity in patients with rheumatic diseases

During recent years atherosclerosis, the major cause of cardiovascular disease (CVD), has been recognised as a chronic inflammatory condition in which rupture of atherosclerotic lesions appears to play a major role. The risk of CVD is raised in many rheumatic diseases. This risk is high in systemic lupus erythematosus - as much as a 50-times increase among middle-aged women has been reported. Studies on CVD and atherosclerosis in rheumatic disease could thus provide interesting information about CVD and atherosclerosis in addition to being an important clinical problem. A combination of traditional and nontraditional risk factors accounts for the increased risk of CVD and atherosclerosis in rheumatic disease. One interesting possibility is that atherosclerotic lesions in rheumatic disease are more prone to rupture than normal atherosclerotic lesions. It is also likely that increased risk of thrombosis may play an important role, not least in systemic lupus erythematosus. Further, it is not clear whether an increased risk of CVD is a general feature of rheumatic disease, or whether this only occurs among subgroups of patients. It should be emphasised that there is an apparent lack of treatment studies where CVD in rheumatic disease is the end point. Control of disease activity and of traditional risk factors, however, appears to be well founded in relation to CVD in rheumatic disease. Further studies are needed to determine the exact role of lipid-lowering drugs as statins. Hopefully novel therapies can be developed that target the causes of the inflammation in atherosclerotic lesions both in rheumatic patients and in the general population.

Diabetes mellitus and insulin resistance in patients with rheumatoid arthritis: risk reduction in a chronic inflammatory disease

OBJECTIVE

To perform a systematic literature review of the potential association among molecular markers of inflammation, alterations in body composition, and insulin resistance (IR), a precursor to type 2 diabetes mellitus (DM), in rheumatoid arthritis (RA) patients. To determine the impact of tumor necrosis factor α (TNFα) as a pivotal proinflammatory cytokine in the pathophysiology of type 2 DM and RA, and the effect of antirheumatic drugs on glycemic control.

METHODS

We performed a search of PubMed to identify articles on IR and body habitus in patients with RA.

RESULTS

Patients with RA had characteristics placing them at high risk for IR and type 2 DM. The incidence and prevalence of type 2 DM in RA was not clearly increased compared with the general population; however, studies suggested that patients with RA are likely to have IR and have increased risk of cardiovascular disease (CVD). The prevalence of type 2 DM and IR could be estimated from reports of risk factors for CVD in RA patients. The TNFα antagonists provided rapid and effective control of RA-related inflammation. Evidence indicated that extended use of TNFα antagonists in RA may provide the additional benefit of improving insulin sensitivity. These treatment-related changes may contribute to an overall reduction in the risk of type 2 DM and CVD in RA patients.

CONCLUSION

Controlling inflammation may improve insulin sensitivity and subsequently reduce the risk of developing type 2 DM in RA patients. This may also reduce the risk of CVD in this high-risk group. Future studies are required to elucidate the relationships between inflammation, body composition, IR, TNFα antagonist use, and the risk of developing type 2 DM in RA patients.

Effect of feeding status on adjuvant arthritis severity, cachexia, and insulin sensitivity in male Lewis rats

We studied the effect of food restriction, overfeeding, and normofeeding on cachexia, inflammatory and metabolic parameters, and insulin sensitivity in chronic adjuvant arthritis (AA) in rats. Food restriction during AA increased circulating ghrelin, corticosterone, decreased leptin, and ameliorated arthrogram score and systemic inflammation compared to normofeeding. Overfeeding worsened arthrogram score and systemic inflammation, and led to lipid accumulation in the liver, but not to alterations of adipokine and ghrelin plasma levels relative to normofeeding. Independently of feeding status, AA induced cachexia, in which modulation of mRNA expressions for appetite-regulating neuropeptides (NPY, AgRP, POMC, CART) in the arcuate nucleus (ARC) does not play a primary role. The overexpression of IL-1β mRNA in the ARC suggests its role in the mechanisms of impaired energy balance during AA under all feeding conditions. Normal HOMA index in all arthritic groups does not indicate the development of insulin resistance by feeding interventions in these rats.

Insulin resistance in rheumatoid arthritis: the impact of the anti-TNF-alpha therapy

Increased prevalence of insulin resistance has been observed in patients with rheumatoid arthritis (RA). High-grade systemic inflammation is implicated in the development of insulin resistance in these patients. Tumor necrosis factor (TNF)-alpha is a potent proinflammatory cytokine that plays a role in the initiation and progression of inflammation and the mechanisms associated with accelerated atherosclerosis in RA. In assessing data immediately prior to and after intravenous infusion of the anti-TNF-alpha monoclonal antibody-infliximab in RA patients on period treatment with this drug attributable to disease refractory to conventional disease-modifying antirheumatic drugs, a dramatic improvement of insulin resistance and insulin sensitivity was observed. A long-term positive effect of TNF-alpha antagonists infliximab and etanercept on insulin resistance in RA patients with severe disease was also reported. These results highlight the importance of therapies that act blocking TNF-alpha function to reduce the mechanisms implicated in the development of the metabolic syndrome observed in RA.

The effect of methotrexate on cardiovascular disease in patients with rheumatoid arthritis: a systematic literature review

OBJECTIVES

Patients with RA have an increased prevalence of cardiovascular disease (CVD). This is due to traditional risk factors and the effects of chronic inflammation. MTX is the first-choice DMARD in RA. We performed a systematic literature review to determine whether MTX affects the risk of CVD in patients with RA.

METHODS

We searched Medline, Embase, Cochrane database, database of abstracts of reviews of effects, health technology assessment and Science Citation Index from 1980 to 2008. Conference proceedings (British Society of Rheumatology, ACR and EULAR) were searched from 2005 to 2008. Papers were included if they assessed the relationship between MTX use and CVD in patients with RA. Two reviewers independently assessed each title and abstract for relevance and quality.

RESULTS

A total of 2420 abstracts were identified, of which 18 fulfilled the inclusion criteria. Two studies assessed the relationship between MTX use and CVD mortality, one demonstrated a significant reduction in CVD mortality and the second a trend towards reduction. Five studies considered all-cause CVD morbidity. Four demonstrated a significant reduction in CVD morbidity and the fifth a trend towards reduction. MTX use in the year prior to the development of RA decreased the risk of CVD for 3-4 years. Four studies considered myocardial infarction, one demonstrated a decreased risk and three a trend towards decreased risk with MTX use.

CONCLUSION

The current evidence suggests that MTX use is associated with a reduced risk of CVD events in patients with RA. This suggests that reducing the inflammation in RA using MTX not only improves disease-specific outcomes but may also reduce collateral damage such as atherosclerosis.

Methotrexate therapy associates with reduced prevalence of the metabolic syndrome in rheumatoid arthritis patients over the age of 60- more than just an anti-inflammatory effect? A cross sectional study

INTRODUCTION

The metabolic syndrome (MetS) may contribute to the excess cardiovascular burden observed in rheumatoid arthritis (RA). The prevalence and associations of the MetS in RA remain uncertain: systemic inflammation and anti-rheumatic therapy may contribute. Methotrexate (MTX) use has recently been linked to a reduced presence of MetS, via an assumed generic anti-inflammatory mechanism. We aimed to: assess the prevalence of the MetS in RA; identify factors that associate with its presence; and assess their interaction with the potential influence of MTX.

METHODS

MetS prevalence was assessed cross-sectionally in 400 RA patients, using five MetS definitions (National Cholesterol Education Programme 2004 and 2001, International Diabetes Federation, World Health Organisation and European Group for Study of Insulin Resistance). Logistic regression was used to identify independent predictors of the MetS. Further analysis established the nature of the association between MTX and the MetS.

RESULTS

MetS prevalence rates varied from 12.1% to 45.3% in RA according to the definition used. Older age and higher HAQ scores associated with the presence of the MetS. MTX use, but not other disease modifying anti-rheumatic drugs (DMARDs) or glucocorticoids, associated with significantly reduced chance of having the MetS in RA (OR = 0.517, CI 0.33-0.81, P = 0.004).

CONCLUSIONS

The prevalence of the MetS in RA varies according to the definition used. MTX therapy, unlike other DMARDs or glucocorticoids, independently associates with a reduced propensity to MetS, suggesting a drug-specific mechanism, and makes MTX a good first-line DMARD in RA patients at high risk of developing the MetS, particularly those aged over 60 years.

Inflammation-associated insulin resistance: differential effects in rheumatoid arthritis and systemic lupus erythematosus define potential mechanisms

OBJECTIVE

Insulin resistance is increased by inflammation, but the mechanisms are unclear. The present study was undertaken to test the hypothesis that decreased insulin sensitivity is differentially associated with mediators of inflammation by studying 2 chronic inflammatory diseases of different pathogenesis, systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA).

METHODS

We measured fasting insulin, glucose, and lipid levels, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor alpha (TNFalpha), and coronary artery calcification in 103 patients with SLE and in 124 patients with RA. Insulin sensitivity was measured using the homeostasis model assessment (HOMA) index.

RESULTS

The HOMA value was higher in RA patients (median 2.05 [interquartile range (IQR) 1.05-3.54]) than in SLE patients (1.40 [0.78-2.59]) (P = 0.007). CRP and ESR did not differ significantly in RA and SLE patients. Body mass index (BMI) was significantly correlated with the HOMA index in both RA (rho = 0.20) and SLE (rho = 0.54), independently of age, sex, race, and current use of corticosteroids. In RA patients, the HOMA index was also significantly positively correlated with IL-6 (rho = 0.63), TNFalpha (rho = 0.50), CRP (rho = 0.29), ESR (rho = 0.26), coronary calcification (rho = 0.26), and Disease Activity Score in 28 joints (rho = 0.21); associations adjusted for age, sex, race, BMI, and current use of corticosteroids remained significant (P < 0.05). In SLE patients, the HOMA index was also significantly correlated with ESR (rho = 0.35) and CRP (rho = 0.25), but not with other variables. The association between the ESR and the HOMA value in patients with SLE remained significant after adjustment for confounding covariates (P = 0.008). In multivariable models, the major contributing factors to the HOMA index were the BMI in SLE patients, and IL-6 and TNFalpha levels in RA patients.

CONCLUSION

The pathogenesis of insulin resistance and its contribution to atherogenesis varies in different inflammatory settings.

Cardiovascular disease in rheumatoid arthritis

PURPOSE OF REVIEW

Individuals with rheumatoid arthritis are at increased risk for morbidity and mortality from cardiovascular disease (CVD). The purpose of this review is to discuss recent advances in our understanding of the pathogenesis, prevalence, treatment, and prevention of accelerated atherosclerotic disease in rheumatoid arthritis.

RECENT FINDINGS

Recent reports have highlighted the increased risk for silent myocardial infarction and sudden death in rheumatoid arthritis, and the potential roles of traditional and nontraditional risk factors for CVD, including abnormal revascularization of damaged peripheral blood vessels and genetic polymorphisms. Several studies have also added important information on the possible role of anti-tumor necrosis factor-alpha therapy, other disease modifying antirheumatic drugs, and nonsteroidal anti-inflammatory drugs in decreasing CVD risk.

SUMMARY

The pathogenic mechanisms involved in accelerated cardiovascular complications in rheumatoid arthritis appear to be complex and multifactorial. Both traditional and nontraditional risk factors potentially contribute to the increased cardiovascular risk. Good control of the inflammation, immunologic disturbances, and metabolic changes seen in rheumatoid arthritis are crucial in the prevention of this potentially lethal complication. There is a need for heightened awareness of the increased risk for silent ischemia, early myocardial infarction, and sudden death. Further exploration of the mechanisms of vascular repair and their potential role in premature atherosclerosis is needed.

Inflammation and its relationship to insulin resistance, type 2 diabetes mellitus, and endothelial dysfunction

In the past decade, clinical, laboratory, and epidemiological research have coalesced to give rise to a new paradigm for understanding type 2 diabetes mellitus (DM). In this review, we present data that DM has an inflammatory etiology and that inflammation plays a role in diabetic complications, especially cardiovascular disease. This new paradigm offers insight into the relationship between DM and obesity. It also suggests possible new avenues of treatment.

Prevalence of the metabolic syndrome is increased in rheumatoid arthritis and is associated with coronary atherosclerosis

Patients with rheumatoid arthritis (RA) have accelerated atherosclerosis. The metabolic syndrome, a cluster of cardiovascular risk factors, identifies cardiovascular risk. We tested the hypotheses that patients with RA have a higher prevalence of the metabolic syndrome, particularly the WHO-defined syndrome that requires insulin resistance, and that this is associated with coronary atherosclerosis. The prevalence of the metabolic syndrome was determined using the modified WHO and NCEP III criteria in 154 patients with RA (88 with early RA and 66 with long-standing RA) and 85 control subjects. Coronary-artery atherosclerosis was detected by electron beam computed tomography. The WHO-defined metabolic syndrome was present in 42% of patients with long-standing RA, 31% with early RA and 11% of controls (P<0.001); the NCEP-defined metabolic syndrome was present in 42% of patients with long-standing RA, 30% with early RA and 22% of controls (P=0.03). Patients with the WHO-defined metabolic syndrome had an increased risk of having higher coronary-artery calcification scores, independent of age and sex (OR=2.02, 95% CI: 1.03-3.97, P=0.04). In conclusion, patients with RA have a higher prevalence of the metabolic syndrome than control subjects. Inflammation-associated metabolic syndrome is a mechanism that may contribute to increased coronary-artery atherosclerosis in RA.

Early treatment reduces the cardiovascular risk factors in newly diagnosed rheumatoid arthritis patients

OBJECTIVE

To investigate subclinical atherosclerosis and the effect of treatment in patients with early rheumatoid arthritis (RA).

PATIENTS AND METHODS

Forty patients with early RA who met the revised American College of Rheumatology (ACR) criteria and disease duration of <1 year were included in the study. Smokers and patients with classical risk factors for atherosclerosis were excluded. The serum levels of total cholesterol (TC), triglycerides, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol were determined in all patients before and after 1 year of therapy. Carotid artery intima-media thickness (IMT) and carotid plaque were measured before and after treatment. RA disease activity was measured using the 28 joint indices score (DAS-28) and clinical improvement was determined by the ACR response criteria. Forty-five age- and sex-matched nonsmoking volunteers were used as controls. All patients were treated with methotrexate and prednisone.

RESULTS

RA patients had a baseline mild dyslipidemia characterized by a decrease in serum HDL-C levels and a high TC/HDL-C atherogenic ratio compared with controls. Both lipid parameters were significantly improved after treatment (P<0.01). Common carotid artery IMTs at baseline were higher in RA patients compared with controls (P<0.05). After 1 year of therapy there was a significant decrease in the IMTs (P<0.001). Thirty-five patients (88%) achieved the ACR 20%, while 30 (75%) reached the ACR 50% response criteria. A significant decrease of DAS-28 was observed after treatment (P<0.03).

CONCLUSIONS

The atherogenic lipid profile and subclinical atherosclerosis are features of early RA, which improved after therapy. Early intervention and control of the disease activity may reduce the risk of atherosclerosis and cardiovascular events in patients with RA.

Aminotransferases are associated with insulin resistance and atherosclerosis in rheumatoid arthritis

BACKGROUND

Serum aminotransferase concentrations are reportedly strongly associated with insulin resistance, an established cardiovascular risk factor that is not routinely assessed in clinical practice. We therefore explored the possibility that serum aminotransferase concentrations are as closely related to large artery disease as insulin resistance in rheumatoid arthritis (RA).

METHODS

Carotid artery plaque (ultrasonography), insulin resistance and liver enzymes (prior to methotrexate (MTX) were determined in 77 consecutive patients with RA (43 with and 34 without MTX).

RESULTS

Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were associated with insulin resistance in univariate analysis (R = 0.54, p < 0.0001 and R = 0.36, p = 0.001, respectively) and after adjustment for age, gender and waist circumference (partial R = 0.43, p = 0.0001 and partial R = 0.37, p = 0.001, respectively). ALT and AST concentrations were higher in patients with plaque as compared to in those without plaque (ALT (u/l): 27 2223242526272829303132 versus 20 181920212223, p = 0.02; AST (u/l): 25 2122232425262728 versus 20 19202122, p = 0.02). The odds ratios [95% CI] for plaque were 1.92 [1.14-3.24] (p = 0.01), 1.93 [1.17-3.16] (p = 0.009) and 1.82 [1.13-2.93] (p = 0.01) for 1 SD increase in ALT (~10 u/l) and AST (approximately 6 u/l) concentrations and in logarithmically transformed homeostasis model assessment of insulin resistance (HOMA-IR) (~0.2 uU.mmol/ml.l), respectively. After adjustment for the potentially confounding characteristics of age, sex, hypertension and hypothyroidism in logistic regression models, ALT (p = 0.049) and AST concentrations (p = 0.027) remained associated with plaque whereas the HOMA-IR did not (p = 0.08). AST concentrations (p = 0.049) were associated with plaque independent of insulin resistance whereas the HOMA-IR (p = 0.1) was not associated with plaque independent of AST concentrations.

CONCLUSION

Within currently recommended reference ranges, serum aminotransferase concentrations may be strongly associated with insulin resistance and atherosclerosis in patients with RA. The measurement of aminotransferase concentrations could be a useful tool in cardiovascular risk stratification in patients with RA.

Insulin resistance is an independent risk factor for atherosclerosis in rheumatoid arthritis

The objective of this study was to investigate the relationship between insulin resistance (IR) and subclinical atherosclerosis in patients with rheumatoid arthritis (RA). Carotid artery intima media thickness (IMT), using ultrasound evaluation, and other clinical and laboratory variables were investigated in 45 RA outpatients and in 48 controls with soft tissue disorders. IR was assayed by homeostasis model assessment (HOMA2) and metabolic syndrome by National Cholesterol Education Program Adult Treatment Panel (NCEP ATP III) criteria. Insulin resistance, as defined by HOMA2-IR>1, was seen in 40 (88.9%) RA patients and in three (6.2%) controls (p<0.001). No significant difference was detected in the prevalence of metabolic syndrome. The median IMT was greater in RA patients (0.76 mm; interquartile range [IQR] 0.65, 0.85) than in the controls (0.66 mm; IQR 0.60, 0.72) (p<0.001). Dividing the RA patients according to the cut-off IMT value (0.72 mm), a difference was detected in both systolic (p=0.04) and diastolic blood pressure (p=0.02), disease activity score (DAS28) (p=0.008), HOMA2-IR (p<0.001) and cumulative oral steroid dose (p=0.001). Moreover, the frequency of cases with increased IMT was higher in glucocorticoid users than in non-users (21/23 vs. 9/22, respectively) (p<0.001). Spearman's rho correlation showed a significant positive relationship between IMT and HOMA2-IR (p<0.001). Multivariate stepwise analysis selected HOMA2-IR plus diastolic BP plus glucocorticoid exposure as the best predictive model for subclinical atherosclerosis (R2c=0.577, F=21, p<0.001). In conclusion, this study showed a significantly higher prevalence of IR in RA patients and pointed out a significant association between IR and subclinical atherosclerosis. This relationship may be driven primarily by exposure to steroid therapy.

The effects of high walnut and cashew nut diets on the antioxidant status of subjects with metabolic syndrome

BACKGROUND

Nut consumption is associated with a protective effect against coronary heart disease, partly due to its high antioxidant content. It is hypothesized that the inclusion of nuts in the diet will improve the antioxidant status of subjects with metabolic syndrome who may be vulnerable to impaired antioxidant status.

AIM

The effects of high cashew nut and high walnut diets on the antioxidant status of subjects with metabolic syndrome are investigated.

METHODOLOGY

Sixty-four volunteers (29 male and 35 female, 45 +/- 10y) with metabolic syndrome (diagnosed by using the ATP III criteria) received a prudent control diet, prepared in the metabolic kitchen of the North-West University, Potchefstroom campus (NWU-PC) for a period of 3 weeks (run-in). The participants were grouped according to gender and age and randomized into three groups, receiving either the walnut, cashew nut or the control diets for 8 weeks, while maintaining a stable body weight. Nuts provided 20% of daily energy intake. Fasting blood samples were taken after the run-in period (baseline) and at the end of the intervention period and analyzed for various antioxidant capacity markers.

RESULTS

The oxygen radical absorbance capacity (ORAC) of the walnut and cashew nut diets were significantly higher than the control diet. Despite this, the walnut and cashew nut diets had no significant effects on serum ORAC, reduced (GSH), oxidized (GSSG) glutathione, GSH:GSSG or diacron reactive metabolites (dRom) (total oxidant status) levels compared to the control group. However, all three groups showed significant improvements in antioxidant status from baseline to end (GSSG and dRom levels decreased; GSG:GSSG ratio and ORAC levels increased). This may be due to a general increased antioxidant intake from the prudent diet compared to the habitual diets.

CONCLUSION

Although the inclusion of walnuts and cashew nuts into a prudent diet resulted in an increased antioxidant capacity (ORAC) of the nut diets, compared to the control diet, it did not improve the serum antioxidant profiles of subjects with metabolic syndrome.

Impact of TNF inhibition on insulin resistance and lipids levels in patients with rheumatoid arthritis

Patients with rheumatoid arthritis (RA) have increased cardiovascular mortality. TNF-alpha is a critical mediator of inflammation and metabolic response in patients with RA. Increased insulin resistance and dyslipidemia were known risk factors in patients with active RA, however, the regulation of these metabolic parameters by TNF-alpha is poorly understood. Neutralization of TNF-alpha with infliximab offers a unique opportunity to study TNF-alpha-mediated regulation of these metabolic parameters in RA. The aim of the study was to assess the in vivo TNF-alpha-mediated regulation of insulin resistance and lipids levels in RA. Nineteen patients with active RA treated with infliximab were prospectively followed for 14 weeks. Plasma lipids levels and insulin resistance were measured at baseline, 6 and 14 weeks after infliximab treatment. At week 14, the disease activity (DAS-28 score) improved significantly (p < 0.000), with a significant reduction in both C-reactive protein (p = 0.007) and erythrocyte sedimentation rate (p = 0.006) levels. The body weight did not change during the study period. After infliximab treatment, insulin resistance improved as reflected by the significant reduction in the Homeostasis Model Assessment Index. Total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, and apolipoprotein B (apoB) levels all increased significantly from baseline. Nonetheless, the atherogenic index, LDL-cholesterol/HDL-cholesterol ratio, and the LDL/apoB ratio remained unchanged. Infliximab improves insulin sensitivity and alters lipid profile in patients with active RA.

Insulin resistance and impaired beta cell function in rheumatoid arthritis

OBJECTIVE

To identify factors that regulate glucose metabolism in rheumatoid arthritis (RA).

METHODS

We evaluated the homeostatic model assessment of insulin resistance (HOMA-IR) and beta cell function (HOMA-B) in 94 RA patients. We investigated the relationship between characteristics known to affect glucose metabolism in the general population (age, abdominal obesity [waist circumference], hypertension, antihypertensive therapy) as well as characteristics of RA (disease activity, glucocorticoid therapy) and insulin resistance and beta cell function.

RESULTS

Patients with high-grade inflammation (high-sensitivity C-reactive protein value >1.92 mg/liter) (n = 81) were more insulin resistant than patients with low-grade inflammation (n = 13), whereas beta cell function was similar in both groups. Insulin resistance and beta cell function were similar in both groups after adjustment for waist circumference. All recorded characteristics except for age were associated with HOMA-IR or/and HOMA-B in univariate analyses. In mixed regression models, abdominal obesity and patient's assessment of disease activity (by visual analog scale) were predictors of insulin resistance. The Disease Activity Score assessed using 28-joint counts for swelling and tenderness, tender joint count, and patient's assessment of disease activity were associated with reduced beta cell function, and the cumulative dose of glucocorticoids was associated with enhanced beta cell function. The cumulative glucocorticoid dose in all study patients was a mean of only 536 mg (95% confidence interval 239-1,173). In patients with high-grade inflammation, age was further associated with impaired beta cell function, whereas use of angiotensin-converting enzyme inhibitors or angiotensin II type 1 receptor blockers was associated with enhanced beta cell function.

CONCLUSION

The modifiable factors of abdominal obesity, antihypertensive therapy, disease activity, and use of glucocorticoids appear to affect glucose metabolism in RA.